First observations of detached equatorial ionospheric plasma depletions using OI 630.0 nm and OI 777.4 nm emissions nightglow imaging

Author(s)

Sahai‚ Y. ; Abalde‚ JR ; Fagundes‚ PR ; Pillat‚ VG ; Bittencourt‚ JA

• Document type: Journal article
• Source: Geophysical Research Letters; v. 33, n. 11, p. L11104, 2006.

Abstract

Near-simultaneous all-sky (180 degrees field of view) observations of the OI 630.0 nm and OI 777.4 nm nightglow emissions are being carried out on a routine basis at "Laboratorio Nacional de Astrofisica (LNA)'', Brazopolis (22.5 degrees S, 45.6 degrees W; dip latitude 17.5 degrees S; altitude 1860 m), Brazil, since September 2002. The all-sky imaging observations of the OI 630.0 nm and OI 777.4 nm emissions, which arise from the dissociative recombination of O-2(+) ions and radiative recombination of O+ ions ( mainly), respectively, are used to monitor the morphology and dynamics of the equatorial F-region at the respective emission heights. In this paper we present and discuss the first observations showing detached equatorial F-region plasma depletions or bubbles. Three cases are presented from observations during the years 2002 and 2003. We suggest a possible mechanism for their generation. (AU)

• FAPESP's process: 05/00084-3 - Study of termosphere-ionosphere coupling at Brazilian sector
• Grantee: José Ricardo Abalde Guede
• Support Opportunities: Regular Research Grants